Speaking to the club's official website, the Dutchman lauded: "The way they [Barcelona] play is impressive. The football they play is out of this world".
"I've played with Xavi, [Carles] Puyol and [Andres] Iniesta, and now they are the backbone of this team.
"When I was there, they were young, it's a real honour and pleasure to see their play bring so much success to the club."
Kluivert also revealed that Guardiola was always destined to be a "great manager", even during his playing days.
"He was already a leader when he was a footballer and you had the intuition that when he finished his career he would be a great manager," added Kluivert.
"He connects with the players. He knows how he wants the team to play and he communicates that well to his players."
The Dutchman also compared the form that Lionel Messi has had for both club and country, and blamed the selfishness of Argentina's football for the stark difference.
"Barca plays for Messi but on the other hand when we see him play for his national side, he's different," he said.
"When Messi plays for Barca he's simply marvellous, but with Argentina there are many players that just play for themselves."
Kluivert played for Barcelona from 1998-2004, scoring 122 goals during his time in Catalunya.